The device is used for didactic teaching of the function of a modern interior light control depending on the door contact switch and the ignition plus. There is also an indicator light for open doors.
After opening a door, the interior light is switched on and switched off again after a certain period of time in order to save the battery power. If the door is closed again during this time, the light is dimmed and switched off after a certain time. Switching on the ignition during this time switches off the interior light immediately. Conversely, when the ignition is switched off, the interior light is switched on and switched off again when a door is opened and closed. The control lamp lights up when a door is open and the ignition is switched on.